The Effect Of Surface Properties And Flow Characteristics To Coalescence Of Oil-water Separation

At present, most of the oilfields in China are being into the high water cut stage. There are a lot of questions following with the high water cut stage. How to develop new technology of separation is the problem that we have to resolve. The filler as the key technology of coalescence should be put more emphasis on.This paper mainly studied the influence of the material of coalescence. First of all, The coalescence mechanism was summarized, as well as the basic rules of coalescence. The author holds that spatial constitution form of the fillers has important effect on the oil removal efficiency of coalescence. And as the collision coalescence mechanism and the wetting coalescence mechanism were coexistent, the efficiency of coalescence was enhanced remarkably. Moreover, the author used the modifiers to improve the surface wettability of the PP which was tested with the self developed device. The laboratory test results indicated that the oil removal performance of material was resulted from both the water contact angle and the oil contact angle. Furthermore, the optimum operation parameters were obtained with the self developed equipment through the test of emulsifying rate, residence time, length of coalescence-plate and surface roughness of coalescence-plate.In addition, the flow field of several different shapes'typical filters are simulated and analyzed by Fluent6.3.Through the analysis of the flow field,the pressure field and track diagram of discrete phase, the coalescence effect of filters can be evaluated and the results can give reference for field application. Simulation results show that the egg-like filter with unique structure can form phenomenon of alternately high and low pressure which can disturb the fluid flow and produce pulsating flow. Then, the chance that collision coalescence happens between oil droplets and filters or oil droplets and oil droplets is greatly enhanced and the efficiency of coalescence is enhanced remarkably. By analyzing simulation results, the defects of all kinds of filters are found. Especially the egg-like filter has the defect of short flow. The author suggests that the plate is rotated 45°to avoid this phenomenon.Finally, the large device was designed based on the results of experiment and simulation. Then experimentize and confirm the results that we got from the experiment and simulation.